SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63e3174049cb84d286f29866ef9ecb4fc069ce618fc175846ba39c455e0bc143' 
  AND token = 'ClQr41IqFzWHxqgKZxWRqeBLf4xILwTzs0IrpqecDBM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}